Anson-Madison Sanitary District's clarifier tank is situated near the Kennebec River in Madison. Credit: Erin Rhoda / BDN

A Maine wastewater treatment plant on the leading edge of removing toxic chemicals from wastewater to prevent them from being flushed into rivers needs $59 million more to fully launch its first-of-a kind removal system, officials from the facility told lawmakers on Wednesday.

The Anson-Madison Sanitary District, which treats waste from the Somerset County towns of Anson and Madison, has been working with engineers for several years to develop a centralized treatment system for waste from across Maine that could remove PFAS and concentrate the chemicals into a more manageable form.

PFAS, which stands for per- and polyfluoroalkyl substances, have been linked to a number of serious illnesses.

The wastewater treatment plant has so far received $11.1 million, including from state and federal sources, to design and operate a PFAS removal system at the pilot scale, Steve Woodard, the chief innovation officer for Portland-based Emerging Compounds Treatment Technologies, or ECT2, told lawmakers.

But the technology and power required to scale up is expensive. To do so, the wastewater treatment plant estimates needing $59 million more in 2024 dollars, adding hard figures to the estimated toll PFAS contamination has taken on Maine.

The project runs the risk of stalling in about three months, Woodard said, in part because costly items need to be ordered soon in anticipation they will take a long time to arrive.

Municipal and commercial wastewater treatment plants currently dispose of their treated wastewater into Maine rivers. They are not set up to clean out PFAS. In addition to ending up in the environment, the chemicals can also then flow into community drinking water supplies that serve thousands, including lawmakers at the Capitol.

ECT2 and Dirigo Engineering have worked with the Anson-Madison Sanitary District to demonstrate over the last few months that it is possible to pretreat its wastewater — which has materials such as dissolved solids, ammonia and heavy metals that can muck up efforts to pull out PFAS — and then remove PFAS from the mix and concentrate the waste through a series of steps, Woodard said.

The PFAS waste is trucked to Crossroads Landfill in nearby Norridgewock. Any contaminated liquid that flows out of the landfill, called leachate, is then returned to the wastewater treatment plant, creating a closed loop that prevents the chemicals from being discharged into the Kennebec River, he said.

The PFAS treatment system is being designed and built to ultimately take in, at a minimum, all of Maine’s leachate, totalling about 500,000 gallons per day, and all of the waste pumped out of septic tanks, called septage, totalling more than 200,000 gallons per day, Woodard said.

“The project is well underway,” Woodard said. “We’re looking to continue that progress and get to the point where the system’s being designed to take all the leachate, all the septage in the state, and treat it and produce drinking water quality.”

The cleaned wastewater is not drinking water, but its resulting PFAS levels fall well below current standards for drinking water before being discharged into the river, Woodard said.

The removal system relies on a number of ways to pull out PFAS from lots of wastewater and concentrate it. For example foam fractionation introduces air and turbulence to create PFAS-filled foam that can be skimmed off as a first step.  

“It’s like putting your water that contains PFAS into a blender,” Woodard said. “It takes that first bite out of the problem.”

The removal system also relies on ion exchange resins, basically tiny plastic beads with special engineered properties, to remove more PFAS than a different popular treatment media, granular activated carbon. Contaminated water gets passed through vessels with millions of these tiny beads, and the PFAS chemicals latch onto them.

A specific solution then releases PFAS from the beads, and a distillation process recovers most of the remaining solution so it can be reused. ECT2 also developed and patented a process called SuperLoading to take the leftover brine with highly concentrated PFAS and reduce the byproduct even further.

The result is a drastic reduction in the volume of PFAS waste, Woodard said, cutting down a million gallons of contaminated wastewater into about a gallon of PFAS waste.

One day the wastewater treatment plant hopes to destroy — or mineralize — PFAS once the chemicals are removed from wastewater. ECT2 has worked with a number of laboratories and companies to figure out which destruction technologies will work best, but they are still under development, Woodard said.

The Anson-Madison Sanitary District is operating at 20 percent capacity because of the closure of Madison Paper Industries in 2016. Instead of building onto a full-capacity wastewater treatment plant, it made more sense and was less expensive to turn to an under-used plant, said Jim Lord, senior civil engineering project manager at Dirigo Engineering. Eventually the wastewater treatment plant hopes to recoup revenue when it can process more outside waste, he said.

The wastewater treatment plant is also within a two-hour drive of 85 percent of the state’s population and nearly every landfill, Woodard said.

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Erin Rhoda

Erin Rhoda is the editor of Maine Focus, a team that conducts journalism investigations and projects at the Bangor Daily News. She also writes for the newspaper, often centering her work on domestic and...